Our daily lives are filled with the need for reading printed material at any time and in any place. Utility bills and mail at home, food labels at the supermarket, clothes labels at the department store, textbooks at school, manuals and reports at work, and menus at restaurants are but a few examples. Nearly 10 million people in the United States have visual impairments which prevent them from reading books or the newspaper, even with the assistance of reading glasses, contacts or magnifiers, and millions more have mental and learning disabilities that severely limit their reading. To these people, their inability to read these materials in the places they are encountered puts them at a severe disadvantage.
Electronic reading machines using computer-based optical character recognition (OCR) have been used since the late 1980's to assist these reading-impaired people. In general, electronic reading machines have comprised personal computers outfitted with computer scanners, optical character recognition software, and computerized text-to-voice hardware or software. Currently, machines are sold by a variety of companies, including Telesensory of Mountain View, Calif., Arkenstone of Sunnyvale, Calif., and Kurzweil Educational Systems of Waltham, Mass. In general, the operation of these systems involves placing text on a scanner and obtaining a pixel bitmap of the page to be read, converting that image to text using an OCR program in the personal computer to which the scanner is attached, and generating speech output of the interpreted text using a text-to-speech software program. In order to navigate through the text on the page, the user either presses keys on the computer keyboard or keys on a special keypad in order to skip forward or backward by word, sentence or paragraph, repeat a section, or otherwise move through the formatted text.
These reading machine systems, unfortunately, suffer from a variety of operational insufficiencies that limit their effectiveness. For instance, before the reading machine can begin to read a page, the user must typically wait over a minute. This delay is due primarily to three causes. Firstly, scanning a page is a mechanical action that takes time to move the electro-optical components over the page. Secondly, the large amounts of information in the scanned image require time to be transmitted to the computer. Thirdly, optical character recognition of an entire page can take considerable time. Thus, if a user wanted to scan through a newspaper or a magazine, considerable time would be needed simply to wait for the each page or scanned sections of text to process to the extent that it could begin audibly reading the text.
Another insufficiency of conventional reading machines is that scanners are limited in the size of page they can process, and reading a newspaper page would require multiple passes through the scanner. Furthermore, the keypad navigation of current reading machines requires that the user move through the text in the same order in which the computer organizes the data. At best, the user can skip over some paragraphs quickly, but the way in which the user is forced to apprehend the data is in the same linear fashion that the computer stores the information. This difficulty is less important in most books, in which the information is largely along a single narrative track, but can be quite limiting with highly formatted text such as newspapers, magazines, scientific journals, bus schedules, utility bills, and advertisements.
The majority of vision-impaired individuals have some residual vision, and many of these people use electronic magnifiers instead of OCR-based electronic reading machines. These magnifying systems generally consist of an electronic video capture system (usually with a CCD camera) connected to a video display. The book to be read is placed on a mechanical tracking mechanism beneath the video capture system, and assists the user in moving the book horizontally so as to keep the current line of text within the field of view of the camera. Means are generally provided to the user to adjust the contrast of the image, invert the colors of the image, and adjust the focus through manual controls on the face of the magnifying systems.
Because people with residual vision feel empowered using their remaining vision, and because they can use the magnifying systems to see information that is outside the scope of reading machines (e.g. seeing graphics on a page), and because they are generally less expensive than electronic reading machines, magnifying systems currently enjoy a far larger market than electronic reading machines. The are a large number of such magnifying systems currently available, including ones from Telesensory of Mountain View, Calif., Magnisight of Colorado Springs, Colo., and Optelec of Westford, Mass. However, conventional magnifying systems suffer from a number of problems.
For example, the mechanisms for tracking lines of text are often difficult to use, since they are manually-guided mechanical systems that require relatively precise and steady hand movements to guide the movement.
This requirement is difficult for certain people, especially the elderly who have fine motor problems, but also because it involves cognitive feedback control at the same time that considerable effort is being devoted to interpreting the images on the screen. Furthermore, when short columns of text are being read, the user must engage in frequent control of both vertical and horizontal mechanical guiding systems. Also, because of the small field of view of the camera and the limited movement of the mechanical system, the page must often be repositioned on the mechanical guides. Because of the small field of view of these systems, it is difficult for the user to understand the overall structure of text and graphics on a complexly formatted page. In addition, the system depends entirely on the user's vision, even though this vision may be adequate only for very slow reading. Yet furthermore, the image manipulations afforded by these systems (e.g. contrast, brightness, zoom and focus) are generally limited, since they depend on mechanical systems and analog electronics, rather than the much greater range of possible effects of a digital system.
It was our intention to solve the problems of the prior art, both with regards to OCR-based electronic reading machines as well as electronic magnifying systems, that gave rise to the current invention.